Diesel engine

Abstract

A diesel engine is provided with an exhaust after-treatment device for purifying exhaust gas. The exhaust after-treatment device includes a DPF that collects a particulate matter included in the exhaust gas, and an SCR that reduces nitrogen oxides included in the exhaust gas through addition of urea. The DPF is arranged to extend in an engine width direction orthogonal to both the engine front-rear direction and an up-down direction, on one side of the engine front-rear direction with respect to the DPF. The DPF and the SCR are attached to the diesel engine.

The invention claimed is: 
     
       1. A diesel engine equipped with an exhaust after-treatment device to purify exhaust gas, wherein
 the exhaust after-treatment device has a first case and a second case for treating the exhaust gas, 
 the first case is located extending in an engine front-rear direction parallel to a crankshaft, 
 the second case is located extending in an engine width direction orthogonal to both the engine front-rear direction and an up-down direction, on one side of the engine front-rear direction with respect to the first case, and 
 the first case and the second case are attached to a cylinder head of the diesel engine, and 
 the first case has an exhaust outlet at an end on a far side from the second case in the engine front-rear direction to discharge the exhaust gas after a particulate matter is collected, and 
 a second case pipe connects the exhaust outlet of the first case and an exhaust inlet of the second case. 
 
     
     
       2. The diesel engine according to  claim 1 , wherein
 the first case is Diesel Particulate Filter (DPF) that collects the particulate matter contained in the exhaust gas, and 
 the second case is a Selective Catalytic Reduction (SCR) that reduces nitrogen oxides contained in the exhaust gas by adding urea. 
 
     
     
       3. A diesel engine equipped with an exhaust after-treatment device to purify exhaust gas, wherein
 the exhaust after-treatment device has a DPF and a SCR for treating the exhaust gas, 
 the DPF is located extending in an engine front-rear direction parallel to a crankshaft and collects particulate matter contained in the exhaust gas, 
 the SCR is located extending in an engine width direction orthogonal to both the engine front-rear direction and an up-down direction, on one side of the engine front-rear direction with respect to the first case, and reduces nitrogen oxides contained in the exhaust gas by adding urea, 
 the DPF and the SCR are attached to a cylinder head of the diesel engine, 
 the DPF has an exhaust outlet at an end on a far side from the SCR in the engine front-rear direction to discharge the exhaust gas after the particulate matter is collected, and 
 an SCR pipe connects the exhaust outlet of the DPF and an exhaust inlet of the SCR. 
 
     
     
       4. A diesel engine equipped with an exhaust after-treatment device to purify exhaust gas, wherein
 the exhaust after-treatment device has a first case and a second case for treating the exhaust gas, 
 the first case is located extending in an engine front-rear direction parallel to a crankshaft, 
 the second case is located extending in an engine width direction orthogonal to both the engine front-rear direction and an up-down direction, on one side of the engine front-rear direction with respect to the first case, 
 the first case and the second case are attached to a cylinder head of the diesel engine, and 
 the diesel engine further comprises a single bracket is provided to secure both the first case and the second case to the diesel engine. 
 
     
     
       5. The diesel engine according to  claim 4 , wherein
 the single bracket has
 a first bracket part to fix the second case to the diesel engine and 
 a second bracket part to fix an end of the first case to the diesel engine, the end being located closer to the second case where the first bracket part is located. 
 
 
     
     
       6. The diesel engine according to  claim 5 , wherein
 the second bracket part has at least a base portion attached to the first bracket part and a mount portion rising from an end of the base portion and attached to the end of the first case closer to the second case, 
 the base portion is attachable to the first bracket part with various postures in which a base portion side of the mount portion faces a first case side and the base portion side of the mount portion faces a second case side, and 
 the mount portion is attachable to the end of the first case closer to the second case at any of a surface on a base portion side of the mount portion and a surface opposite to the base portion side of the mount portion. 
 
     
     
       7. The diesel engine according to  claim 6 , wherein
 the base portion is attached to the first bracket member via a fastening member that is inserted through a long hole formed in the base portion. 
 
     
     
       8. The diesel engine according to  claim 5 , wherein
 the first bracket member is attached directly or via a spacer to a mounting member fixed to a flange provided on the second case.